Attempt a new approach to isolating corn histone genes by preparing from corn tissues (early endosperm and freshly sprouting seedlings) mRNA shown by suitable procedures to code for histones. We will make cDNA from this mRNA for use in rescreening the corn shotguns for histone genes. Complete sufficient DNA sequence of Mm 30.5 (Science 202, 1978, 1279-1289) to determine the sequence of the protein encoded by it and to establish whether or not the gene contains a small intervening sequence. Attempt to determine whether the unusual 30.5 gene is located in the genome in the same vicinity as are the normal alpha globin genes. Characterize, by DNA sequencing, clone 142.7 (isolated from the mouse shotgun) which contains sequences related to the micron immunoglobulin constant region and to the J regions. Attempt to determine the nature of the events which lead to the duplication of the two human fetal globin genes, G gamma and A gamma, by sequencing appropriate parts of the human DNA clone 165.24 (Slightom, Blechl, Smithies. Manuscript in preparation).